Angular distributions of recoil products from some reactions induced in 65Cu and 197Au by protons of energy 30–85 MeV

Abstract

Angular distributions of products formed in the reactions 65Cu(p,pn)64Cu, 197Au(p,pn)I96Au, and 197Au(p,p3n)194Au in the range of proton energy 30–85 MeV were studied. The angular distribution results of 64Cu and 196Au show forward peaking at low energy and sidewise peaking at higher energies. Approximate symmetry about 90° was observed for the angular distribution of 194Au in the center-of-mass system. The experimental results have been compared with (a) Monte Carlo evaporation calculations, (b) cascade–evaporation calculations at 85 MeV for 64Cu, and (c) inelastic scattering plus evaporation calculations.Good agreement was obtained with statistical theory calculations at low energy and inelastic scattering model calculations at higher energies. The comparisons indicate that the reactions proceed by the compound nucleus mechanism at lower energies and the direct interaction mechanism predominates at higher energies.